Create App Links for Instant Apps

An Android Instant App is a small version of your app that runs without
installation. Instead of installing an APK, users launch your app simply by
clicking a URL. As such, all instant apps need to be accessible via a URL
declared using Android App Links. This page explains how to use Android App
Links for your Android Instant Apps.

Note: If you're not building an instant app, then you don't need to read this
guide—you should instead create app links for your installable app by reading
Create Deep Links to App Content.

App links overview

First, here's a summary of what you should already understand about app links.

When you create an intent filter for activities in your app that allow
the user to jump straight to a specific screen in your app with a
URL link, this is known as a "deep link." Other apps can declare a similar
URL intent filter, though, so the system might ask the user which app to
open. To create these deep links, read
Create Deep Links to App Content.

When you publish an assetlinks.json file on the website that corresponds
to your app's HTTP deep links, you verify that your app is the true owner
of those URLs. Thus, you've converted your deep links into Android App Links,
which ensure that your app instantly opens when the user clicks such a URL.
To create app links, read
Verify Android App Links.

So, Android App Links are simply HTTP deep links that your website is verified
to own so that the user doesn't need to choose which app to open. For a more
specific description, see differences between deep links and app links.

In both cases, however, the user must already have your app installed. If the
user clicks one of your web site's links and they don't have your app installed
(and no other app handles that URL intent), the URL is opened in a web browser.
So, creating an Instant App solves this part—it allows users to open your app by
simply clicking a URL, even if they don't have your app installed.

When end users perform a Google search for your app, Google Search displays a
URL with the "Instant" badge.

Notice that you don't need to include the host in the second <data>
element because, within each <intent-filter> element, all combinations of
each <data> attribute are considered valid (so this intent filter does
resolve https://www.example.com).

Other reminders when creating app links

All HTTP URL intent filters in your instant app should be included
your installable app. This is important because once the user installs your
full app, tapping a URL should always open the installed app, not the instant
app.

You must set autoVerify="true" in at least one intent filter in both the
instant and the installable app. (See how to enable automatic verification.)